Currently, in a hybrid fiber-coaxial (HFC) network system, downlink data is sent on a downlink channel in a broadcast manner, and uplink data is transmitted based on resource scheduling of a network device. That is, after receiving an uplink transmission request sent by user equipment, the network device may allocate a transmission resource to the user equipment, and deliver allocation information of the transmission resource to the user equipment using a scheduling packet. In addition, the scheduling packet also needs to be sent on the downlink channel in a broadcast manner. Therefore, when the network device receives a large quantity of uplink transmission requests, a transmission bandwidth of the scheduling packet increases accordingly. If a system provides a fixed total bandwidth of the downlink channel, a bandwidth of downlink data is reduced, and therefore downlink data transmission is seriously affected.